Twenty-year Trend in Mortality among Hospitalized Patients with Pneumococcal Community-Acquired Pneumonia

Abstract

There is only limited information on mortality over extended periods in hospitalized patients with pneumococcal community-acquired pneumonia (CAP). We aimed to evaluate the 30-day mortality and whether is changed over a 20-year period among immunocompetent adults hospitalized with pneumococcal CAP. We conducted a retrospective observational study of data that were prospectively collected for adult patients diagnosed with pneumococcal CAP at our university teaching hospital over a 20-year period. To aid analysis, results were divided into four periods of 5 years each (1997–2001, 2002–2006, 2007–2011, and 2012–2016). The primary outcome was 30-day mortality, but secondary outcomes included intensive care unit (ICU) admission, lengths of hospital and ICU stays, ICU mortality, and need of mechanical ventilation. From a cohort of 6,403 patients with CAP, we analyzed the data for 1,120 (17%) adults with a diagnosis of pneumococcal CAP. Over time, we observed decreases in the rates of alcohol consumption, smoking, influenza vaccination, and older patients (age ≥65 years), but increases in admissions to ICU and the need for non-invasive mechanical ventilation. The overall 30-day mortality rate was 8% (95% confidence interval, 6%–9%; 84 of 1,120 patients) and did not change significantly between periods (p = 0.33). Although, we observed a decrease in ICU mortality comparing the first period (26%) to the second one (10%), statistical differences disappeared with adjustment (p0.38). In this large prospective cohort study of adults hospitalized with pneumococcal CAP over a 20-year period, we found no evidence that 30-day mortality had decreased over time.